A good place to read on the evolution of organs

Hi, (I think I started a thread similar to this earlier) I was wondering if anyone knows of any good websites or books or DVD's that focus on the evolution of organs and organ systems. That is, the point at which a group of cells stopped being a "blob" and started differentiating into organs with separate functions (I'm sure this has a name, but I don't know what it is so I don't know what to look for lol).

Hi, (I think I started a thread similar to this earlier) I was wondering if anyone knows of any good websites or books or DVD's that focus on the evolution of organs and organ systems. That is, the point at which a group of cells stopped being a "blob" and started differentiating into organs with separate functions (I'm sure this has a name, but I don't know what it is so I don't know what to look for lol).

Yes, the name of the science that studies how "blobs" of cells become differentiated into first tissues then organs then organ systems is called "embryology", and the specific topic you want to read about is called "morphogenesis"--see this link:http://www.answers.com/topic/morphogenesis

mor·pho·gen·e·sis (môr'fō-jĕn'ĭ-sĭs) n.
The differentiation of cells and tissues in the early embryo which results in establishing the form and structure of the various organs and parts of the body.

thanks for the national geographic article :) . that's along the lines of what was looking for.
I understand how different body parts and organs can evolve through simple steps (eyes, legs, all that), but what I'm having trouble with is how single cells started working together... how did a single celled organism, hundreds of millions of years ago, "decide" to replicate itself many times-- but to have all those cells interact with each other, instead of just floating off alone like its predecessors.
and how did these cells start to have different functions within the same body. ... I mean, all organs and animals with organs must have evolved from some sort of rudimentary organ system -- a group of genetically identical cells that somehow started to perform different functions as one body.